<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
 <meta>
  <!-- Stylesheets -->
  <link href="../web.css" type="text/css" rel="stylesheet"></link>
  <link href="../pygmentize.css" type="text/css" rel="stylesheet"></link>
  <title>VLFeat - Documentation - Matlab API</title>
  

  <!-- Scripts-->
  
 </meta>

 <!-- Body Start -->
 <body>
  <div id="header">
   <!-- Google CSE Search Box Begins -->
   <form action="http://www.vlfeat.org/search.html" method="get" id="cse-search-box" enctype="application/x-www-form-urlencoded">
    <div>
     <input type="hidden" name="cx" value="003215582122030917471:oq23albfeam"></input>
     <input type="hidden" name="cof" value="FORID:11"></input>
     <input type="hidden" name="ie" value="UTF-8"></input>
     <input type="text" name="q" size="31"></input>
     <input type="submit" name="sa" value="Search"></input>
    </div>
   </form>
   <script src="http://www.google.com/coop/cse/brand?form=cse-search-box&amp;lang=en" xml:space="preserve" type="text/javascript"></script>
   <!-- Google CSE Search Box Ends -->
   <h1><a shape="rect" href="../index.html" class="plain"><span id="vlfeat">VLFeat</span><span id="dotorg">.org</span></a></h1>
  </div>
  <div id="headbanner">
   Documentation - Matlab API
  </div>
  <div id="pagebody">
   <div id="sidebar"> <!-- Navigation Start -->
    <ul>
<li><a href="../index.html">Home</a>
</li>
<li><a href="../download.html">Download</a>
</li>
<li><a href="../doc.html">Documentation</a>
<ul>
<li><a href="mdoc.html" class='active' >Matlab API</a>
</li>
<li><a href="../api/index.html">C API</a>
</li>
<li><a href="../man/man.html">Man pages</a>
</li>
</ul></li>
<li><a href="../overview/tut.html">Tutorials</a>
</li>
<li><a href="../applications/apps.html">Applications</a>
</li>
</ul>

   </div> <!-- sidebar -->
   <div id="content">
    
    
<b></b><ul>
<li><b><a href="VL_COMPILE.html">VL_COMPILE</a></b> Compile VLFeat MEX files</li><li><b><a href="VL_DEMO.html">VL_DEMO</a></b> Run all demos</li><li><b><a href="VL_HARRIS.html">VL_HARRIS</a></b> Harris corner strength</li><li><b><a href="VL_HELP.html">VL_HELP</a></b> VLFeat MATLAB Tooblox</li><li><b><a href="VL_NOPREFIX.html">VL_NOPREFIX</a></b> Create a prefix-less version of VLFeat commands</li><li><b><a href="VL_ROOT.html">VL_ROOT</a></b> Obtain VLFeat root path</li><li><b><a href="VL_SETUP.html">VL_SETUP</a></b> Add VLFeat Toolbox to the path</li></ul>
<b>AIB</b><ul>
<li><b><a href="VL_AIB.html">VL_AIB</a></b> Agglomerative Information Bottleneck</li><li><b><a href="VL_AIBCUT.html">VL_AIBCUT</a></b> Cut VL_AIB tree</li><li><b><a href="VL_AIBCUTHIST.html">VL_AIBCUTHIST</a></b> Compute histogram over VL_AIB cut</li><li><b><a href="VL_AIBCUTPUSH.html">VL_AIBCUTPUSH</a></b> Quantize based on VL_AIB cut</li><li><b><a href="VL_AIBHIST.html">VL_AIBHIST</a></b> Compute histogram over VL_AIB tree</li></ul>
<b>GEOMETRY</b><ul>
<li><b><a href="VL_HAT.html">VL_HAT</a></b> Hat operator</li><li><b><a href="VL_IHAT.html">VL_IHAT</a></b> Inverse vl_hat operator</li><li><b><a href="VL_IRODR.html">VL_IRODR</a></b> Inverse Rodrigues' formula</li><li><b><a href="VL_RODR.html">VL_RODR</a></b> Rodrigues' formula</li></ul>
<b>IMOP</b><ul>
<li><b><a href="VL_DWAFFINE.html">VL_DWAFFINE</a></b> Derivative of an affine warp</li><li><b><a href="VL_IMARRAY.html">VL_IMARRAY</a></b> Flattens image array</li><li><b><a href="VL_IMARRAYSC.html">VL_IMARRAYSC</a></b> Scale and flattens image array</li><li><b><a href="VL_IMDISTTF.html">VL_IMDISTTF</a></b> Image distance transform</li><li><b><a href="VL_IMDOWN.html">VL_IMDOWN</a></b> Downsample an image by two</li><li><b><a href="VL_IMGRAD.html">VL_IMGRAD</a></b> Image gradient</li><li><b><a href="VL_IMINTEGRAL.html">VL_IMINTEGRAL</a></b> Compute integral image</li><li><b><a href="VL_IMREADBW.html">VL_IMREADBW</a></b> Reads an image as gray-scale</li><li><b><a href="VL_IMREADGRAY.html">VL_IMREADGRAY</a></b> Reads an image as gray-scale</li><li><b><a href="VL_IMSC.html">VL_IMSC</a></b> Scale image</li><li><b><a href="VL_IMSMOOTH.html">VL_IMSMOOTH</a></b> Smooth image</li><li><b><a href="VL_IMTEST.html">VL_IMTEST</a></b> T</li><li><b><a href="VL_IMUP.html">VL_IMUP</a></b> Upsample an image by two</li><li><b><a href="VL_IMWBACKWARD.html">VL_IMWBACKWARD</a></b> Image backward warping</li><li><b><a href="VL_IMWHITEN.html">VL_IMWHITEN</a></b> Whiten image</li><li><b><a href="VL_RGB2XYZ.html">VL_RGB2XYZ</a></b> Convert RGB color space to XYZ</li><li><b><a href="VL_TPS.html">VL_TPS</a></b> Compute the thin-plate spline basis</li><li><b><a href="VL_TPSU.html">VL_TPSU</a></b> Compute the U matrix of a thin-plate spline transformation</li><li><b><a href="VL_WAFFINE.html">VL_WAFFINE</a></b> Apply affine transformation to points</li><li><b><a href="VL_WITPS.html">VL_WITPS</a></b> Inverse thin-plate spline warping</li><li><b><a href="VL_WTPS.html">VL_WTPS</a></b> Thin-plate spline warping</li><li><b><a href="VL_XYZ2LAB.html">VL_XYZ2LAB</a></b> Convert XYZ color space to LAB</li><li><b><a href="VL_XYZ2LUV.html">VL_XYZ2LUV</a></b> Convert XYZ color space to LUV</li><li><b><a href="VL_XYZ2RGB.html">VL_XYZ2RGB</a></b> Convert XYZ to RGB</li></ul>
<b>KMEANS</b><ul>
<li><b><a href="VL_HIKMEANS.html">VL_HIKMEANS</a></b> Hierachical integer K-means</li><li><b><a href="VL_HIKMEANSHIST.html">VL_HIKMEANSHIST</a></b> Compute histogram of quantized data</li><li><b><a href="VL_HIKMEANSPUSH.html">VL_HIKMEANSPUSH</a></b> Push data down an integer K-means tree</li><li><b><a href="VL_IKMEANS.html">VL_IKMEANS</a></b> Integer K-means</li><li><b><a href="VL_IKMEANSHIST.html">VL_IKMEANSHIST</a></b> Compute histogram of quantized data</li><li><b><a href="VL_IKMEANSPUSH.html">VL_IKMEANSPUSH</a></b> Project data on integer K-means paritions</li><li><b><a href="VL_KMEANS.html">VL_KMEANS</a></b> Cluster data using k-means</li></ul>
<b>MISC</b><ul>
<li><b><a href="VL_ALLDIST2.html">VL_ALLDIST2</a></b> Pairwise distances</li><li><b><a href="VL_ALPHANUM.html">VL_ALPHANUM</a></b> Sort strings using the Alphanum algorithm</li><li><b><a href="VL_ARGPARSE.html">VL_ARGPARSE</a></b> Parse list of parameter-value pairs</li><li><b><a href="VL_BINSEARCH.html">VL_BINSEARCH</a></b> Maps data to bins</li><li><b><a href="VL_BINSUM.html">VL_BINSUM</a></b> Binned summation</li><li><b><a href="VL_COLSUBSET.html">VL_COLSUBSET</a></b> Select a given number of columns</li><li><b><a href="VL_GETPID.html">VL_GETPID</a></b> Get MATLAB process ID</li><li><b><a href="VL_GRAD.html">VL_GRAD</a></b> Compute the gradient of an image</li><li><b><a href="VL_HISTMARG.html">VL_HISTMARG</a></b> Marginal of histogram</li><li><b><a href="VL_HOMKERMAP.html">VL_HOMKERMAP</a></b> Homogeneous kernel map</li><li><b><a href="VL_IHASHFIND.html">VL_IHASHFIND</a></b> D</li><li><b><a href="VL_IHASHSUM.html">VL_IHASHSUM</a></b> M</li><li><b><a href="VL_INTHIST.html">VL_INTHIST</a></b> Calculate Integral Histogram</li><li><b><a href="VL_KDTREEBUILD.html">VL_KDTREEBUILD</a></b> Build randomized kd-tree</li><li><b><a href="VL_KDTREEQUERY.html">VL_KDTREEQUERY</a></b> Query KD-tree</li><li><b><a href="VL_LBP.html">VL_LBP</a></b> Local Binary Patterns</li><li><b><a href="VL_LBPFLIPLR.html">VL_LBPFLIPLR</a></b> Flip LBP features left-right</li><li><b><a href="VL_LOCALMAX.html">VL_LOCALMAX</a></b> Find local maximizers</li><li><b><a href="VL_NUMDER.html">VL_NUMDER</a></b> Numerical derivative</li><li><b><a href="VL_NUMDER2.html">VL_NUMDER2</a></b> Numerical second derivative</li><li><b><a href="VL_OVERRIDE.html">VL_OVERRIDE</a></b> Override structure subset</li><li><b><a href="VL_PEGASOS.html">VL_PEGASOS</a></b> PEGASOS linear SVM solver</li><li><b><a href="VL_SAMPLINTHIST.html">VL_SAMPLINTHIST</a></b> Sample integral histogram</li><li><b><a href="VL_SIMDCTRL.html">VL_SIMDCTRL</a></b> Toggle VLFeat SIMD optimizations</li><li><b><a href="VL_TWISTER.html">VL_TWISTER</a></b> Random number generator</li><li><b><a href="VL_VERSION.html">VL_VERSION</a></b> Obtain VLFeat version information</li><li><b><a href="VL_WHISTC.html">VL_WHISTC</a></b> Weighted histogram</li><li><b><a href="VL_XMKDIR.html">VL_XMKDIR</a></b> Create a directory recursively.</li></ul>
<b>MSER</b><ul>
<li><b><a href="VL_ERFILL.html">VL_ERFILL</a></b> Fill extremal region</li><li><b><a href="VL_ERTR.html">VL_ERTR</a></b> Transpose exremal regions frames</li><li><b><a href="VL_MSER.html">VL_MSER</a></b> Maximally Stable Extremal Regions</li></ul>
<b>PLOTOP</b><ul>
<li><b><a href="VL_CF.html">VL_CF</a></b> Creates a copy of a figure</li><li><b><a href="VL_CLICK.html">VL_CLICK</a></b> Click a point</li><li><b><a href="VL_CLICKPOINT.html">VL_CLICKPOINT</a></b> Select a point by clicking</li><li><b><a href="VL_CLICKSEGMENT.html">VL_CLICKSEGMENT</a></b> Select a segment by clicking</li><li><b><a href="VL_FIGASPECT.html">VL_FIGASPECT</a></b> Set figure aspect ratio</li><li><b><a href="VL_LINESPEC2PROP.html">VL_LINESPEC2PROP</a></b> Convert PLOT style line specs to properties</li><li><b><a href="VL_PLOTFRAME.html">VL_PLOTFRAME</a></b> Plot feature frame</li><li><b><a href="VL_PLOTGRID.html">VL_PLOTGRID</a></b> Plot a 2-D grid</li><li><b><a href="VL_PLOTPOINT.html">VL_PLOTPOINT</a></b> Plot 2 or 3 dimensional points</li><li><b><a href="VL_PLOTSTYLE.html">VL_PLOTSTYLE</a></b> Get a plot style</li><li><b><a href="VL_PR.html">VL_PR</a></b> Compute precision-recall curve</li><li><b><a href="VL_PRINTSIZE.html">VL_PRINTSIZE</a></b> Set the print size of a figure</li><li><b><a href="VL_ROC.html">VL_ROC</a></b> Compute ROC curve</li><li><b><a href="VL_TIGHTSUBPLOT.html">VL_TIGHTSUBPLOT</a></b> Tiles axes without wasting space</li></ul>
<b>QUICKSHIFT</b><ul>
<li><b><a href="VL_FLATMAP.html">VL_FLATMAP</a></b> Flatten a tree, assigning the label of the root to each node</li><li><b><a href="VL_IMSEG.html">VL_IMSEG</a></b> Color an image based on the segmentation</li><li><b><a href="VL_QUICKSEG.html">VL_QUICKSEG</a></b> Produce a quickshift segmentation of a grayscale or color image</li><li><b><a href="VL_QUICKSHIFT.html">VL_QUICKSHIFT</a></b> Quick shift image segmentation</li><li><b><a href="VL_QUICKVIS.html">VL_QUICKVIS</a></b> Create an edge image from a Quickshift segmentation.</li></ul>
<b>SIFT</b><ul>
<li><b><a href="VL_DSIFT.html">VL_DSIFT</a></b> Dense SIFT</li><li><b><a href="VL_PHOW.html">VL_PHOW</a></b> Extract PHOW features</li><li><b><a href="VL_PLOTSIFTDESCRIPTOR.html">VL_PLOTSIFTDESCRIPTOR</a></b> Plot SIFT descriptor</li><li><b><a href="VL_SIFT.html">VL_SIFT</a></b> Scale-Invariant Feature Transform</li><li><b><a href="VL_SIFTDESCRIPTOR.html">VL_SIFTDESCRIPTOR</a></b> Raw SIFT descriptor</li><li><b><a href="VL_UBCMATCH.html">VL_UBCMATCH</a></b> Match SIFT features</li><li><b><a href="VL_UBCREAD.html">VL_UBCREAD</a></b> Read Lowe's SIFT implementation data files</li></ul>
<b>SLIC</b><ul>
<li><b><a href="VL_SLIC.html">VL_SLIC</a></b> SLIC superpixels</li></ul>
<b>SPECIAL</b><ul>
<li><b><a href="VL_DDGAUSSIAN.html">VL_DDGAUSSIAN</a></b> Second derivative of the Gaussian density function</li><li><b><a href="VL_DGAUSSIAN.html">VL_DGAUSSIAN</a></b> Derivative of the Gaussian density function</li><li><b><a href="VL_DSIGMOID.html">VL_DSIGMOID</a></b> Derivative of the sigmoid function</li><li><b><a href="VL_GAUSSIAN.html">VL_GAUSSIAN</a></b> Standard Gaussian density function</li><li><b><a href="VL_RCOS.html">VL_RCOS</a></b> RCOS function</li><li><b><a href="VL_SIGMOID.html">VL_SIGMOID</a></b> Sigmoid function</li></ul>

    















































































































   
   </div>
   <div class="clear">&nbsp;</div>
  </div> <!-- pagebody -->
  <div id="footer">
   &copy; 2007-12 Andrea Vedaldi and Brian Fulkerson
  </div> <!-- footer -->

  <!-- Google Analytics Begins -->
  <script xml:space="preserve" type="text/javascript">
   //<![CDATA[
    var localre = /vlfeat.org/;
    if(document.location.host.search(localre) != -1)
    {
   var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");
   document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));
   }
   //]]>
  </script>
  <script xml:space="preserve" type="text/javascript">
    //<![CDATA[
    var localre = /vlfeat.org/;
    if(document.location.host.search(localre) != -1)
    {

   try {
   var pageTracker = _gat._getTracker("UA-4936091-2");
   pageTracker._trackPageview();
   } catch(err) {}

   }
   //]]>
  </script>
  <!-- Google Analytics Ends -->
 </body>
</html>

 